Large quantities of oil are presently transported from oil-producing regions to oil-consuming regions by various means, including large sea-going vessels. As the number and size of such vessels increases, the probability of a large oil spill occurring, with its attendant, serious environmental consequences also increases. A number of such accidents have occurred which have resulted in contamination of beaches with possibly permanent environmental damage.
Substantial progress has been made in the recovery of oil spilled on large bodies of water. Typically, the oil spill is surrounded by a floating boom to contain the spill. Conventional vacuuming and filtering equipment are then employed to remove the oil from the circumscribed area, as the oil will continue to float on the surface of the water as long as the more volatile components of the oil have not evaporated. Such efforts have proven effective as long as the oil remains at sea, the booms are quickly deployed, and the sea is not too rough.
Recovering oil from beaches is substantially more difficult than recovering oil from the sea. The beach environment contains a large number of organisms which live on the beach, and below the surface of the beach to a depth of approximately one foot. In contrast, the upper layer of the ocean is a relatively "dead" ecological environment. Therefore, oil spills which have washed up on beaches generally cause significantly greater ecological damage than oil spills which are contained at sea.
Unfortunately, no currently known technologies have been successful in recovering oil directly from beaches in an ecologically acceptable manner. Presently, the most effective method of cleaning oil contaminated beaches is to wash the spilled oil back into the ocean so that the boom and vacuum method described above can be employed. This technique is only successful if the oil spill is fresh (i.e., the volatiles have not evaporated). If the oil has begun to evaporate, the beach deposit becomes a heavy sludge which can only be washed off with steam or extremely hot water at high pressure. This combination destroys the beach and is injurious to the organisms which live on and under the beach.
The above-described technique of washing spilled oil back into the ocean is generally accomplished with high pressure hoses. This technique in itself has been recognized as being ecologically harmful in U.S. Pat. No. 4,410,426 to Cloutier. Cloutier describes a device which locally floods a selected area of a beach to suspend spilled oil in a slick above the sand. A conventional skimming device then removes the oil slick. Cloutier's technique requires prodigious amounts of water, heavy equipment, and substantial setup time and therefore is not amenable to rapid deployment to locations distant from industrialized areas where oil spills often occur. Without such rapid deployment capability, the oil spill is likely to viscosify before the equipment arrives rendering Cloutier's technique unusable.
In view of the above, a need exists for a self-contained, rapidly deployable system which can effectively remove oil deposited on a beach, including the surface beneath the beach, without substantially disturbing the physical structure of the beach or killing the organisms which reside thereunder.